I have a small shop building leaking water in where the walls meet the foundation. Here is how they built it, please help me figure out how to fix it! There is a concrete slab. About 10 inches IN from the edge of the flat slab they attached 2x4s, and built the walls up from there. From the outside you can see flat slab, then edge of 2x4, then ¾ inch to the siding. Now the flat slab sticking 10 inches outside collects the rain and it leaks/wicks right under into the building between the slab and the 2x4, beginning to wick up the wall inside and rot the building and its contents. HELP! How do I fix this! I live in a very rainy place..